Pest that Kills Ash Trees Discovered in Four More Maryland Counties; State Expected to Fall under Federal Quarantine Soon

June 22, 2015

Emerald Ash Borer is destroying ash trees across the country.

ANNAPOLIS, MD – The Maryland Department of Agriculture (MDA) has confirmed the presence of the invasive, highly destructive emerald ash borer (EAB) beetle in four more counties, including two on the Eastern Shore: Baltimore, Harford, Dorchester and Queen Anne’s counties. The discovery is expected to bring the state under a federal EAB quarantine.

“We were hoping the EAB would bypass the Eastern Shore, though, frankly we are not surprised to detect its arrival,” said Agriculture Secretary Joe Bartenfelder. “This invasive pest has been aggressive and unrelenting, and we have worked very hard just to slow it down. We will continue to look for new ways to attack this pest and protect these ash trees that are so ubiquitous across Maryland.”

In 2011, MDA enacted a quarantine prohibiting the movement of hardwood from the 14 counties west of the Chesapeake Bay and Susquehanna River to the Eastern Shore. The quarantine was designed to protect the Eastern Shore counties from getting the EAB for as long as possible. The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) once considered EAB state quarantines to be distinct, individual quarantines; however, in 2012, APHIS issued a Federal Order (or policy change) that treated contiguous EAB quarantine areas as a single quarantine area rather than multiple smaller ones, even if it crossed state borders. This policy change allows companies and people to move ash materials within the quarantined area, including across state lines, as long as the entire trip, from start to finish, remains within a contiguous federal quarantine boundary. If, at any point, such a trip leaves a quarantined area, the shipment needs a permit. With the recent discovery of the EAB on the Eastern Shore, MDA expects the State of Maryland to become a part of the federal quarantine. Once that happens, MDA intends to rescind the state quarantine, which will no longer be needed.

The EAB is an invasive wood-boring beetle, native to China and eastern Asia. It probably arrived in North America hidden in common wood packing materials. It was first detected in the United States in 2002 and arrived in Maryland in 2003. Since then, the EAB, which is known to travel by attaching itself to hardwood, has steadily made its way across the state, killing, damaging and defoliating thousands of ash trees. Ash trees are one of the most common landscaping trees used in the United States and are common in western Maryland forests. Ash is also the most common tree in Baltimore, accounting for about 5.9 million of the metro area’s 6.6 million trees.

To combat the destructive beetle, MDA began releasing biocontrol agents – that is, other insects that can attack and kill the EAB in 2009. MDA will be releasing them again this year in at least four areas, though a fifth may be added later in the season. The four sites are in Charles, Anne Arundel (2) and Howard counties. MDA has released more than 210,000 parasitoids in eight counties since 2009, with continued releases in the future.

In addition, MDA encourages homeowners, campers, vacationers, and outdoor enthusiasts not to move firewood and, perhaps, accidentally help spread the EAB. When it comes to firewood, burn it where you buy it.